Today, a feature that often is discussed is the area of switching calls and the like is local switching or local connectivity in communications network. This feature allows calls to be locally switched within a site of a wireless communications networks, such as GSM, WCDMA, LTE or the like. For example, in the GSM the calls are locally switched within a site, in general, three cells, of a Radio Base Station, RBS. This means that the user data of a call is not transferred all the way from a RBS to a Base Station Controller, BSC, and back to the RBS, but rather switched within the site of the RBS. It should here be understood that a site may comprise a number of base stations being located nearby one another providing one cell or a number of cells.
This feature reduces the amount of needed capacity and, consequently, costs for the operator since the speech does not need to be transmitted on the radio interface between the RBS and the BSC, that is, the Abis interface. The Abis interface transports signaling protocols as well as compressed speech.
Local switching of calls may as well be performed within a site of a different network, such as a WCDMA, LTE network or the like, wherein a call is switched within a site of a node B or an evolved node B.
In order to enable the feature of local switching within a site of a base station, such as a RBS, Node-B or the like, of a wireless communications system, additional hardware and software need to be implemented into the base station. Consequently, if there is no or a very small amount of locally switched traffic within a site there is no need to implement these additional components and by determining if no or a very small amount is locally switched transmissions one may save costs by not doing the implementations. To determine if/how much traffic that is possible locally switched traffic within a site, one preferably measures how much traffic stays within the site, that is, are local transmissions.
However, it is very hard to measure how much traffic that is local traffic within a site. One way is to determine that traffic is locally switched by analyzing identity information of a Call Data Records, CDR, from an operator. The CDR contains user information, such as, ID of the caller and the callee, and so on, information that is very sensitive due to user integrity. As the information is very sensitive CDRs are not available or accessible for people and departments planning, building, selling communications networks and it is hard to determine what transmissions over a network that are connected to each other.